Repeater system.



J. H. BELL.

REPEATER SYSTEM.

APPLICATION FILED M16. 1916.

Patented Feb. 26, 1918..

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J OHN H. BELL, OF EAST ORANGE, NEW JERSEY, AS$IGNUE TO illl'hEVJI'ICPRN'ELECTRIG COM- PANY, INCORPORATED, 01'' NEW YORK, N. Y., A COR-PQLRATIOHOF NEW YGRK.

REPEA'I'ER SYSTEM.

Specification of Letters Patent.

Patented Feb. 26, 1918.

Application filed May 16, 1916. Serial No. 97,763.

To all whom it may concern:

Be it known that 1, JOHN H. BELL, a subject of the King of GreatBritain, residing at East Urauge, in the county of Essex and State ofNew Jersey, have invented certain new and useful Improvements inRepeater Systems, of which the following is a full, clear, concise, andexact description.

This invention relates to telegraph systems and more particularly toimprovements in so-called repeater systems whereby, in as sociation withtwo or more independent line circuit sections or signaling circuits,current action first taking place in one circuit section isautomatically relayed into the other circuit sections, such repeatingoperations being reciprocal with respect to a plurality of linesections. The repeater system Which comprises this invention is adaptedfor use with telegraphic codes or arrangements wherein the signal unitsor current impulses are separated by no-current intervals.

The principal object of this invention is to simplify the arrangementofrepeater circuits for a system of the above character, in order topermit the employment of devices of least complication of parts and topro vide that each line section forming one of a dual or multiplecircuit group may be identically equipped with respect to each other asregards repeating devices, and to avoid the necessity of employingapparatus locally common to a group of repeating devices. The lastmentioned feature permits of greater flexibility in the interconnectingand grouping of circuit or sections for rendering service of thischaracter, owing to the fact that the repeating equipment of one linesection is typical'of the equipment of each one of the other linesections associated therewith.

In accordance with this invention, each signaling or main line sectionmaking up the telegraphic line or system is provided with two polarizedrelays and one alternating or universal current relay, each directlyresponsive to the currents which traverse the associated main linecircuit .section. The switching contacts of the universal current relayof one line section are arranged to control the operating circuits ofthe repeating relays common to the other line sections comprising arepeating group. Accordingly, when originating or controlling currentimpulses, separated by no-current intervals, are

other line sections are disabled, While the repeating relays of theprimarily active sectlon operate to include a suitable source of currentat the repeating point to set up current changes and no-currentintervals in the other sections, corresponding in character to thechanges set up in the first section. This system is adapted to relay socalled single current or double current signaling combinations, and maybe employed for either operating printing telegraphs or for manualtelegraph working.

In the accompanying drawing, Figure 1 illustrates diagrammatically a.repeater equipment in accordance with this invention, whereby thereciprocal .relaying of signals may be effected from one to the other oftwo main line sections, and Fig. 2 similarly illustrates a multiplerepeater equipment suitable for reciprocally relaying signals from onesection to the other section of a multiple line group formed of threeline sections.

The features of this invention may be readily understood from adescription of the operation of the system. Referring first to Fig. 1,let it be assumed that the ends (not shown) of the main line conductors1 and 2 terminate in ditferent stations and that each terminal isequipped with apparatus suitable for sending or receiving messages ofthis character.

In accordance with well-known telegraphic practice, telegraph printingsystems may be operated by signaling impulses formed of intermittentapplications of current of the same polarity, also by current impulsesof changing polarity, all of which may be applied to a main line sectionby the transmitter at a sending station thereon. Such characteristiccurrent impulses, in turn, being translated into a printed message at areceiving station, all in a manner well-known in the art. Assuming nowthat such impulses supplied from suitable sources of grounded batteryare present in the line circuit 1 at a distant station (not shown), itwill be apparent these currents may complete circuit through thecontacts 15 of a polarized relay 13, the coeperating contacts andarmature of an alternating current relay 12, the winding of a secondalternating current relay 5, the winding of a polarized relay 6, thencethrough the winding of a second polarized relay 7 to the earthconnection. The relay 5 is responsive to each character of currentaction through the circuit traced and, being adapted to respond quicklywhen energized and to release slowly when de'nergized, it remainsoperated under the usual cessations of current present at certaininstants in the spacing or changing of polarity with respect to thetransmitted impulses; therefore, during the time a message is beingtransmitted over the line 1, the contacts of this relay remainseparated, thereb disconnecting the into the line circuit 1 are the sameas those already described, except that the operations take placethrough similar action of other relays. In tracing such a message,currents repeating group, comprlsing relays 12, 13 from the line 2complete circuit through the and 14. Although the relay 5 continuesencontacts 8 of the polarized relayfi, the conergized by the transmittedimpulses, the tact and armature of the relay 5, the windsame currentthrough the polarized relays 6 ingof the alternating current relay 12,and 7 act selectively therein to suitably thence to earth through theserially-contranslate each impulse of current. The ponected windings ofthe polarized relays '13 .larized relays are biased to render theirreand 14. During the time current action is spective normal contacts 8and 10 closed in present in the line circuit 2, the relay 12 unison witheach cessation of current in the line 1 such as takes place in thespacing of impulses or between reversals in current direction.Accordingly, in response to intermittent impulses of positive current,the relay 6 will be operated to set up corresponding separations andclosures, respectively, of its contacts 8 and 9 during which time -nooperating effect is, however, produced in the other polarized relay 7,except to incidentally add some increase of pressure to the normalbiasing'force acting to close its .contacts 10. Therefore, the rela 7remains inert under positive impulses 0 current, while the relay 6responds thereto in phase with such impulses.

The relayed currents may be traced by assuming that, under the influenceof a posltive impulse of current oyer the main line section 1, the relay7 remains inert while the relay 6 is operated, thereby causing theseparation of its contacts 8 and the closing of its contacts 9 wherebythe positive pole of a grounded battery 19 is connected to the lineconductor 2, and accordingly energizes this line in unison with theoriginating impulses in the line 1. Now, if immedlately following thepositive impulse or impulses,

- an impulse of negative current is received from the main lineconductor- 1, the relay 6 is restored and remains inert, while thenegatively poled relay 7 is operated to separate its contacts 10 andclose its contacts 11, thereby connecting an oppositely poled groundedbattery 20 to send a corresponding negative impulse of current out overthe hne conductor 2.

The arrangement whereby the contacts 8 of the relay 6 are connected inparallel with the contacts 10 of the relay 7, and the correspondingrelation of the contacts 17 of the relay 14 with respect to'the contacts15 of the relay 13, while not an essential feature of this system, isemployed only for the reason that in practice it is expedient that theserelays be of uniform type, therecontinues energized, thereby separatingits contacts to disconnect the repeating .group comprising relays ,5, 6and 7. The polarized relays 13 and 14 now selectively respond to theimpulses present in the line circuit 2, in

the same manner as hereinbefore described for the correspondingoperations of the relays 6 and 7. The closing of the contacts 16 of therelay 13, in response to a positive impulse, connects the positive sideof the grounded battery 19 to the line conductor 1, Accordingly, underan impulse of ne ative current the line circuit 2, the re ay 13 restoresand remains inert, while the relay 14 is operated to close its contacts18, thereb including the negative side ofthe 'groun ed battery 20 withthe line conductor 1.

From the. foregoing description, it will be readily understood that,during the time messages are being transmitted from the line circuit 1,the roup of relays designated as B are disable while the relayscomprising the group A are active to repeat the message into the line 2,and conversely, when a message is transmitted from the line circuit 2,the repeating group A is disabled, while the group 2 is actlve to repeatthe message into shown) on this line. The path of these currents may betraced through the cooperating contact 50 and armature of a universalcur rent relay 47, the contact 38 and armature of a universal currentrelay 37, a conductor 32, the winding of a polarized relay 25, thewinding of a second polarized relay 26, a conductor 33, thence to earththrough the Winding of an alternating or universal cur rent relay 27.The relay 27 is energized by these currents to continuously separate itscontacts 28 and 30, and to close its contacts 29 and 31 during thepassage of signal surrent impulses. The various circuit changes set upby the operation of the relay 27 are first, the separation of itscontacts 28 disconnects the repeating group D comprising relays 35, 36and 37, all corresponding with the line 22; second, the separation ofits contacts 30 disconnects the repeating group E comprising relays 45,46 and 47, all corresponding with the line 23; third, the closing of thecontacts 29 connects the line circuit 22 to the common or bus conductor34 of the relays 25 and 26; and fourth, the closing of the contacts 31connects the line circuit 23 also to the bus conductor 34, therebyestablishing a physical connection between the line circuits 22 and 23.Now, at the instant a positive impulse of current is received over theline circuit 21, the polarized relay 25 remains inert, while theassociated polarized relay 26 is operated to close its contacts, therebyincluding the positive pole of the grounded battery 19 with the busconductor 34, thence this current branches into the main line circuits22 and 23. The path of the repeated impulse for the line 22 may betraced from the bus conductor 34 over the contacts 29 of the relay 27 aconductor 42, and the contacts 48 of the relay 47, while thecorresponding impulse of current from the bus conductor 34 reaches theline 23 over the contacts 31 of the relay 27. At the instant an initialimpulse of negative current is transmitted over the line circuit 21, thepolarized relay 26 is restored to remain inert, while the polarizedrelay 25 is operated to close its contacts, thereby including thenegative pole of the grounded battery 20 with the bus conductor 34, fromwhich point this repeated current reaches the main line circuits 22 and23 over the respective paths already traced for the positive im-- pulseof current from the battery 19.

The foregoing description of the operations taking lace when a messageis repeated from t e line 21 to the lines 22 and 23 is typical of theaction takin place when a message is repeatedfrom eit er one of thelatter line circuits to the other two lines. from the line 22 to thelines 21 and 23, the repeating group D is active, while the re peatinggroups C and E are respectively disconnected by the separation of thecontacts 38 and 40 of the alternating current relay 37. The currentimpulses set up in the line circuit 22 may be traced therefrom by way ofthe contacts 48 of the relay 47, a conductor 42, the contacts 28 of therelay 27, a conductor 52, the serially connected windings of 'thepolarized relays 35 and 36, a

Accordingly in repeating signal conductor 44, thence through the Windingof the alternating current relay 37 to the earth connection. In responseto this cur rent action in the line 22, the polar relays 35 i and 36selectively connect the associated batteries by way of the bus conductor54 to the line circuit 21 over the contacts 39 of the relay 37, and thecontacts 50 of the relay 47, and to the line circuit 23 by way of thecontacts 41 of the relay 37 and the contacts 30 of the relay 27.

Messages originating in the line circuit 23 in a similar manner operatethe repeating group E, comprising relays 45, 46 and 47, to first disablethe repeating groups C and D and, secondly, to cause the polarized relay45 and 46 to connect the associated batterles to set up repeatedimpulses of current in the llnes 21 and 22, all by way of contacts andconductors corresponding with those already traced.

From the foregoing description, it will be apparent that with thepresent system, the repeating equlpment of one line circuit is typicaland a counterpart of the equi ment of each one of the other linecircuits associated therewith to form a repeating roup.

Although several batteries have, for convenlence, been shown in thedrawing, it will be understood that each set of correspondngly poledbatteries may be, and preferably 1s, one and the same battery.

What is claimed is:

1 In a telegraph repeating system, a plurahty of telegra h linecircuits, sources of current, a plura ity of line relays for each linecircuit for repeating telegraphic signals from any one of said linecircuits into the other ones of said line circuits, and contacts on saidrelays efl'ective in said repeatmg operations to translate telegraphicintervals corresponding with predetermined periods of no current.

2. In a telegraph repeating system, a plurality of current sources, aplurality of telegraph line circuits, a universal current line relay anda first and second polarized line.

relay for each one of said line circuits, contacts operated by theuniversal current relay of any line circuit for disabling the linerelays of the other line circuits and for joining the other linecircuits one with another, and contacts operated by the polarized relaysof any line circuit for repeating telegraphic signals corresponding withpredetermined periods of positive current, of negative current andcessation of current into the other ones of said line circuits.

3. In a telegraph repeating system, a plurality of telegraph linecircuits, a repeating device normally connected to each line circuit,and adapted to receive signals over the line to which it is connected, asource of current, means controlled by each repeating device fordisconnecting another repeatingdevice from its line and forintermittently connecting the source of current to the other linecircuits in response to the si als received 'over the line circuit towhich it is connected.

4.- In a telegraph repeating system, a plurality of telegraph linecircuits, a repeating device normally connected to each line circuitcomprisin a plurality of relays, adapted to receive signals over theline to which they are connected, a source of current, means controlledby each repeating device for disconnecting another repeating device fromits line and for intermittently connecting the source of current to theother line circuits in response to the signals received over the circuitto which it is connected.

cuit, comprising a plurality of polarized relays and a universal currentrelay, said relays being adapted to receive signals from the ine circuitto which they are connected, a source of current, means controlled bythe universal current relay for disconnecting another repeating devicefrom its line throughout the receipt of a series of signals over theline to which it is connected, and means controlled by the polarizedrelays for intermittently connecting the source of current to the otherline circuits in response to said signals. In witness whereof, Ihereunto subscribe my name this 12th day of May A. D. 1916.

JOHN. ii. BELL.

